Fuel pump of internal-combustion engines



H. R. RlcARoo FUEL PUMP OF INTERNAL COMBUSTION ENGINES Feb. 5, 1929.

Filed March 8, 1928 2 Sheets-Sheet Feb. 5, 1929.

H. R. RICARDO FUEL PUMP 0F INTERNAL COMBUSTION ENGINES' V Filed March '8, 1928 2 Shets-Sheet 2 resented Feb. s, 1929. -A

PATENT FFICE.

EABBY RALPH BICABDD, F LONDON, ENGLAND.

FUEL PUMP 0F INTERNAL-COIBUSTION ENGINES.

Application med Iaroh 8, 1928, Serial No. 200,080, land in Great Britain April 13, 1927.

This invention relates to sleeve valve internal combustion engines employing liquid fuel injection and of the type in which each sleeve has a combined oscillating and recipro- 6 catingmotion im arted thereto b means of a floating lever or; am to one polnt in which is imparted a substantially rotary motion by means of an eccentric or crank pin, a second point in the lever being connected to the 10 sleeve, for eirample through a spherical or other exible cou ling, while the leveris constrained at a thir point by a slide or by a link connected at one end to the lever and pivoted at the other end to the crank case or some l5 other fixedpart of the engine.

The object of the present invention is to provide improvedmechanism for operating `and controlling the fuel injection pump or pumps of such an engine.

According to the present invention the plunger of a fuel pump in an engine of the above type is operated through suitable ,mechanism from the floating lever or beam through which motion is imparted to the sleeve valve. When the invention is applied to a multi-cylinder internal combustion engine the plunger of each fuel ump is conveniently operated from the oating lever which actuates the sleeve valve in the cylinder l to which the fuel pump delivers fuel. Other arrangements may, however, be employed if desired.

' In either case when the floating lever or beam is constrained at one point by a pivoted link the plunger of the fuel pump is conveniently operated by such link while the suction valve or the suction valve and a separate spill valve controlling an overflow passage are operated by cams or eccentrics mounted 40 on arotary shaft driven from the crank shaft. This shaft conveniently also constitutes the pivot or fulcrum for the pivoted link. The engine is conveniently of the type in which -the fuel is injected without atomizing air through a fuel injection device having an automatically operatedfuel injection valve, the fuel pump being of the kind in which the middle portion of each pressure stroke only is employed to inject the fuel, the end portions of each pressure stroke being rendered inoperative by opening the suction valve or a separate spill valve at such times.

The pump plunger is preferably adapted to be operated during its pressure stroke by the horizontal swinging motion of the floating lever or beam, in which case the arrangement is conveniently such that the beam is travelling with substantially its greatest horizontal velocity during the actual period of injection thus causing a correspondingly rapid injection of the fuel.

With an engine according to this invention it will be seen that the heavy shock-like loads imposed by the pump plunger when the operative portion of its pressure stroke takes place are taken by the relatively heavy sleeve operating linka e.

The invention may be carried into practice in various ways but one construction according to this invention is illustrated by way of example in the accompanying drawings, in which Figure l is a cross-sectional elevation showing the o erating mechanism for the fuel pump, an

Figure 2 is a similar view on an enlar ed scale showing the construction of the el Sump and the manner in which the valves are isposed and operated.

In the construction illustrated the engine so comprises a water-cooled cylinder A having inlet and exhaust ports A1, A2 in its wall controlled by a sleeve valve B disposed and moving within the cylinder. Within the sleeve valve B reciprocates the piston C. The sleeve valve B has a combined oscillating and reciprocating motion imparted thereto by mechanism comprising a floating lever or beam D one end of which is connected, for exam le through a spherical joint or other flexi le coupling. to the sleeve as indicated at E. To a point in the beam D intermediate in its length is imparted a rotary motion by means of a crank pin F on a crank shaft F1, this crankv pin engaging a suitable bearing in the beam D. The crank shaft F1 is driven at half crank shaft speed through suitable gearing. The other end ofthe beam D is connected by a pivot Gr1 to the end of one arm Gzof a two-armed link or lever G pivoted at Gr3 to 100 The fuel pump plliinger J passes through a. guide J1 and operates within a suitable bore J 2 in a housing or casing J 3. Formed in the upper end of the housing J1x is the pressure chamber J 1 of the pump, this chamber being closed by a screw-tl Jaded cap J 5 containin an automatic delivery valve J of the ba type controlling the delivery of fuel through the delivery passage J7 leading to the fuel sprayer J 8. Fuel is fed to the pressure chamber J4 through a suction or inlet valve K of the poppet or like type control ling an inlet or suction passage K1, the stem- K2 of this valve being provided at its lower end with a cap K3 against which bears a spring K4 tending to maintain the valve alwa s closed. The suction valve K is adapted to e opened positively by means of a push rod or tappet L controlled by a spring L1 and adapted to be operated by an eccentric or cam L2 on a shaft La which 1s driven by suitable gearing from the crank shaft and serves also as the pivot for the link or lever G.

Between the up er end of the tappet L and the cap K3 on the ower end of the valve stem K2 is disposed a tapered member M pivoted at M1 to a support' M2 which is capable of being rocked about a pivot M3 by means of a screwthreaded link M4 passing through a socket member M5 and provided with an adjusting screw M and lock nut M. It will be seen that by rocking the support M2 the tapered member M can be moved so that it acts as a distance piece of different widths between the members K3 and L and thus varies the moment of opening and closing of the suction valve K. If desired a second valve similar to K and operated in asimilar manner by a cam or eccentric on the shaft L2 ma be provided acting as a spill valve control 'ng an overflow passage from the pressure chamber of the pump, the suction valve or the suction and spill valves being so operated in known manner that only the centre portion of each pressure stroke of the plunger J is effective to deliver fuel through the valve J 1 in the delivery passage.

It will be seen that with fuel pump operating mechanism according to the present invention, the heavy shock-like loads produced when thc fuel pump plunger elfects injection of fuel are taken by the linkage mechanism for operating the sleeve valve which in any case has to be relatively heavy, thus removing the necessity for providing separate relatively heavy mechanism for operating the plunger of the fuel pump.

It is to be understood that the constructional details may be varied without departing from this invention'and that although the invention has been described with articular reference to engines in which the oatin lever or beam is constrained at one point y a pivoted link, it may also be applied to engincs in which one point in the floating lever is constrained to move substantially in a straight line by a slide or the like.

lVhat I claim as my invention and desire to secure by Letters Patent is l. An vinternal combustion engine of the liquid fuel injection type including in combination, a c linder, a sleeve valve within the cylinder, a ever, means for imparting circular motion in a plane parallel to the c 1inder axis to one point in the length o the lever, means for constraining another point in the lever to follow a determined; path, a flexible operative connection between a third point in the lever and the sleeve whereby a combined oscillating and reciprocating motion is imparted to the sleeve, a fuel pump plunger, and an operative connection between the lever and the plunger whereby the plunger is caused to reciprocate in accordance with themovements of the lever.

2. -An internal combustion engine of the liquid fuel injection type including in combination, a cylinder, a sleeve valve within the cylinder, a lever, a movable member which is constrained to follow a determined path, an operative connection between one point in the Y lever and this member, a means for imparting circular motion in a plane parallel to the cy inder axis to another point inthe lever, an operative connection between a third point in the lever and the sleeve whereby a combined oscillating and reciprocating motion will be imparted to the sleeve, a fuel pump plunger, and an operative connection between the plunger and the movable member whereby the plunger will be caused to reciprocate in accordance with the movements of the lever.

3. An internal combustion engine of the liquid fuel injection type including in combination a cylinder, a sleeve valve within the cylinder, a lever, a link pivoted at one end to a fixed part and at the other end to one point in the lever, means for imparting a circular motion in a plane parallel-to the. cylinder axis to another point in the lever, an operativeV connection between a third point in the lever and the sleeve valve whereby a combined oscillating and reciprocating motion will be imparted to the sleeve, a fuel pump plunger, and an operative connection between the plunger and the link whereby the plunger will be caused to reciprocate in accordance with movements of this link. l

4. An internal combustion engine of the j i liquid fuel injection type including in combination a cylinder, a sleeve valve Within the erative connection between the other arm of v the two-armed lever and the plunger whereby the plunger will be reciprocated in 'accordance with the movements of this lever.

5. An internal combustion engine of the liquid fuel injection type including in combination, a cylinder, a sleeve valve within the cylinder, a lever, a link pivoted at one end to a fixed part and at the other end to one point in the lever, means for imparting circular mot-ion in a plane parallel to the cylinder axis to another point in the lever, a flexible operative connection between a third point in the lever and the sleeve valve whereby a cornbined oscillating and reciprocating motion will be imparted to the sleeve, a fuel pump comprising a cylinder, a plunger within the cylinder and at least one relief valve controlling an overflow port in they cylinder, an operative connection between the link and they plunger whereby the plunger will'be caused to reciprocate in accordancewith movements of this link, a cam shaft constituting a pivot for the fixed end of the link, means for rotating the camshaft and a cam on the camshaft acting on each relief valve so as to render the earlier and later portions of each plunger delivery stroke inoperative as set forth.

6. An internal vcombustion engine of the liquid fuel injection type including in combination a cylinder, a sleeve valve within the cylinder, a floating lever, a two-armed lever pivoted to a fixed part, a pivotal connection between one arm of the two-armed lever and a point in the floating lever, means for imparting circular motion in a plane parallel to the cylinder axis to another point in the floating lever, an operative connection between a third point in the floating lever and the sleeve valve whereby a combined oscillating and reciprocating motion will be imparted to vthe sleeve, a fuel injection pump comprising a cylinder, a. piston within the cylinder and at least one relief valve controlling an overflow port in the cylinder, anoperative connection etween the other arm of the two-armed lever and the plunger whereby the plunger is caused to reciprocate in accordance with movements of the lever, a cam shaft acting as the pivot for the two-armed lever, means for rotating the camshaft and a cam on the camv shaft acting on each relief valve so as to render the earlier and later portions of each pump delivery stroke inoperative as set forth.

7.' A multi-cylinder internal combustion engine of the liquid fuel injection type inl clnding in combination a plurality of cylinthe sleeve, means for constraining another.

point in the lever to follow a definite path, a lay shaft, eccentrics on the lay shaft engaging respectively a third point in each lever, means for rotating the lay shaft whereby each lever will be causedtomove so as to impart a combined oscillating and reciprocating motion to its associated sleeve, a separate fuel pump for supplying fuel to each cylinder comprising a cylinder and a plunger within the cylinder, and an operative connection between each plunger and the lever associated with the engine cylinder to which the fuel pump Supplies fuel whereby the plunger is caused to reciprocate in accordance with the movements of the lever.

8. A multi-cylinder internal combustion engine of the liquid fuel injection type including in combination a plurality of cylinders, a sleeve valve in each cylinder, a lever associated with each sleeve, an operative connection between one point in the lever and the sleeve, a link,

pivoted at one end to a fixed part and at they other end to another point in the lever, a lay shaft, eccentrics on the lay shaft engaging respectively a third point in each lever, means for rotating the lay shaft whereby each lever will be caused to move so as to impart a combined oscillating and reciprocating motion'to its associated sleeve, a separate fuel pump for supplying fuel to each engine cylinder 4comprising a cylinder and a plunger within the cylinder, and an operative connection between each plunger and the link associated with the valve operating mechanism of the cylinder to which the fuel pump supplies fuel whereby the plunger is caused to reciprocate in accordance with the movements of the link. i v

9. A multi-cylinder internal combustion engine of the liquid fuel injection type including in combination a plurality of cylinders, a sleeve valve in each cylinder, a`

each engine cylinder comprising a cylinder,

a plunger within the cylinder .and at least one relief valve controlling an overflow port in the cylinder, 'an operative connection between each link and its associated plunger whereby the plunger Will be reciprocated in accordance with the movements of the link, a cam shaft constituting a pivot for the 5 fixed ends of all the links, means for rotating the cam shaft and cams on the cam shaft actingrespectively. on the relief valves so as to render the earlier and later portions of each plunger delivery stroke inoperative as set forth.

In testimony whereof I have signed my name to this specification.

HARRY RALPH RICARDO. 

